The present invention relates to a method for producing a surface mounting optoelectronic component comprising a base body, an optoelectronic transmitter and/or receiver that is arranged in a recess of the base body, and an optical device that occludes the recess, as well as to a surface mounted optoelectronic component.
In recent years, surface mounting technology (SMT) has increasingly supplanted the equipping of conductor carriers with wired components. The crucial advantage of SMT is an increase in packing density, which cannot be achieved by conventional insertion methods.
Due to the high packing density, which is desirable in many optical applications, SMT is particularly important in the field of optoelectronics. There are already known optoelectronic components which are designed to be surface mounting in accordance with the SMT concept.
European Patent Application No. EP 0 230 336 A1 describes a surface mounting optoelectronic component that comprises an annular housing, the upper opening of which is sealed by a ball lens, while the lower opening of the ring stands on a printed circuit board. Inside the housing, a light-emitting semiconductor element is arranged between the circuit board and the bottom vertex of the ball lens. The interior space of the ring housing, which is defined by the surface of the printed board and the ball lens, is filled with a transparent glue.
Another surface mounting optoelectronic component is illustrated in European Patent Application No. EP 0 400 176. This component has a base body with a central depression in which an optically active semiconductor element is arranged. Above the base body, there is a lens, which is connected to the base body via a fixing mechanism such as a clamping peg.
“Siemens SMT-TOPLED für die Oberflächenmontage” (Frank Möllmer and Günter Waitl, Siemens Components 29 (1991), Vol. 4:147-149) teaches a light emitting diode (LED) which is provided for surface mounting. To produce this diode, a continuously stamped conductor strip is coated with a thermally stable thermoplast, forming the housing frame. In the inner region of the housing frame, an optically active element is mounted on the conductor strip and electrically contacted to interconnects there. Next, the frame's interior region for guarding the active element against environmental influences is cast using a casting resin. A lens or similar optical device is not provided in this component.
The SMT opto-components described in the documents cited above have the unique attribute that first the whole component housing is produced by coating a conductor strip with a thermoplast material, and the opto-electronic transmitter and/or receiver is inserted into the thermoplast housing only after this is produced. The advantages of this method of production are that a very economical mass production at the belt (conductor strip) is possible, and low structural heights and standardized basic structural forms are easy to realize. Due to their low costs, these prehoused SMT opto-components, as they are called, are used above all in display arrays and the like.